Selective RF device activation

• US 8,674,809 B2
• Filed: 07/18/2012
• Issued: 03/18/2014
• Est. Priority Date: 07/20/2005
• Status: Active Grant

• Current Assignee: Zest Labs, Inc.
• Original Assignee: Intelleflex Corporation
• Inventors: Bares, William Henry, Paley, Daniel Noah, Schlicht, Lauren Marie
• Primary Examiner(s): Zimmerman, Brian
• Assistant Examiner(s): Khan, Omer S
• Application Number:
  US13/552,514
• Publication Number:
  US 20120319824A1
• Time in Patent Office: 608 Days
• Field of Search: 340/10.3, 340/10.31, 340/10.32, 340/825.52, 370/349
• US Class Current: 340/10.3
• CPC Class Codes: G06F 1/12 Synchronisation of different clock signals provided by a plurality of clock generators
• CPC Class Codes: G06F 1/3209 Monitoring remote activity, e.g. over telephone lines or network connections
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: G06K 19/0705 the battery being connected to a power saving arrangement
• CPC Class Codes: G06K 19/0707 the arrangement being capable of collecting energy from external energy sources, e.g. thermocouples, vibration, electromagnetic radiation G06K19/0702 takes precedence
• CPC Class Codes: G06K 19/0712 the arrangement being capable of triggering distinct operating modes or functions dependent on the strength of an energy or interrogation field in the proximity of the record carrier active means for hindering electromagnetic reading or writing G06K19/07336
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06Q 10/08 Logistics, e.g. warehousing, loading or distribution; Inventory or stock management
• CPC Class Codes: H04W 52/0238 where the received signal is an unwanted signal, e.g. interference or idle signal
• CPC Class Codes: H04W 52/028 switching on or off only a part of the equipment circuit blocks
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Systems and methods for activating one or more devices are disclosed. According to one embodiment, the device listens for an activate code, the activate code having a length field and a mask field, the mask field including a mask value, the length field specifying a length of the mask field to a final bit of the mask value. Upon receiving the activate code, the length field is compared to a stored length value for determining whether the length field meets a predefined criterion. If the length field meets the predefined criterion, an address of the activate value is loaded (if an address field is present) and the appropriate bits (mask value) of the mask field are compared to a stored activate value. An activate signal is generated if the mask value matches the stored activate value. The activate signal can be used to activate additional circuitry including the entire device.

Claims

1. A method for activating a device, comprising:

listening for an activate code;

receiving the activate code, the activate code having a length field and a mask field following the length field, the mask field including a mask value, the length field having a length value specifying a length of the mask field as a specific numerical value of bits to a final bit of the mask value, thereby specifying a position of the final bit of the mask value in the mask field;

comparing the length value in the length field to a stored length value for determining whether the length field meets a predefined criterion;

comparing the mask value in the mask field to a stored activate value upon determining that the length field meets the predefined criterion; and

activating additional circuitry upon determining that the mask value matches the stored activate value;

remaining in a hibernate state upon determining that the mask value does not match the stored activate value,

wherein the predefined criterion is that the length value of the length field is greater or less than the stored length value,

wherein the activate code is preceded by an interrupt signal, and further comprising detecting the interrupt signal and performing the method upon detecting the interrupt signal,

wherein the mask value in the mask field is compared to the stored activate value on a bit-by-bit basis as the activate code is received, and

wherein at least one of the fields of the activate code is programmable, wherein authorization is required prior to programming the at least one of the fields.

2. A method as recited in claim 1, wherein the predefined criterion is that the length value of the length field is greater than the stored length value.

3. A method as recited in claim 1, wherein the predefined criterion is that the length value of the length field is not greater than the stored length value.

4. A method as recited in claim 1, wherein the mask value is not compared to the stored activate value if the length field does not meet the predefined criterion, wherein the additional circuitry is not activated.

5. A method as recited in claim 1, wherein the activate code further includes an address field, wherein the address field is received prior to the mask field, the address field indicating a start position of the mask value in the mask field of the activate command.

6. A method as recited in claim 5, wherein the mask field is of a predefined length, wherein the method fails if the length field and address field result in a roll-over when comparing the stored activate value to the mask value.

7. A method as recited in claim 5, wherein the mask field is a circular mask, wherein if the length field and address field result in a roll-over, the stored activate value is compared to bits in the mask field in a circular manner.

8. A method as recited in claim 1, wherein the device is a radio frequency identification (RFID) tag, wherein the specific numerical value of bits to the final bit of the mask value is a numerical bit position of the final bit of the mask value in the mask field.

9. A method as recited in claim 8, wherein RFID tag is a passive tag.

10. A method as recited in claim 8, wherein RFID tag is an active tag.

11. A method as recited in claim 1, wherein the method is performed by several RFID tags, wherein only a portion of the tags compare the mask value in the mask field to a stored activate value upon receiving a particular activate code.

12. A Radio Frequency Identification (RFID) system, comprising:

a plurality of RFID tags configured to perform the method of claim 1; and

an RFID interrogator in communication with the RFID tags.

13. A method as recited in claim 1, wherein the activate code is preceded by a clock synchronization signal.

14. A method as recited in claim 1, further comprising changing the stored length value for use in a subsequent communication.

15. A method as recited in claim 1, further comprising changing the stored activate value for use in a subsequent communication.

16. A method as recited in claim 1, wherein the authorization includes verification of a password.

17. A method as recited in claim 1, further comprising terminating the comparison upon comparing the final bit of the mask field as specified by the length field.

18. A method as recited in claim 1, further comprising remaining in the hibernate state when the length field does not meet the predefined criterion.

19. A method as recited in claim 1, wherein the length value of the length field is equal to at least one of (i) a number of bits from a first bit following the length field to a final bit of the mask value, and (ii) a number of bits from a first bit of the mask field to the final bit of the mask value.

20. A method as recited in claim 1, wherein the predefined criterion is that the specific numerical value of bits defined by the length value of the length field is numerically greater or less than the stored length value.

21. An RFD tag, comprising:

a circuit configured to perform the method as recited in claim 1; and

a memory for storing the stored activate value.